Luis Suarez faces being thrown out of the World Cup after Fifa officially charged him with biting Giorgio Chiellini as Uruguay eliminated Italy to make their way into the knockout stages.

Suarez walked to the team bus laughing but refusing to comment on whether he had bitten the Juventus defender.

Later he said: "These are things that happen on the pitch, we were both in the area, he thrust his shoulder into me.

"These things happen on the pitch, and we don't have to give them so much (importance)."

The pair clashed in the 79th minute. Despite the fact that Chiellini exposed his shoulder to reveal clear bite marks, the Mexican referee Marco Rodriguez did not spot the incident, which Fifa launched an investigation into hours after the match. Uruguay now have until 5pm (9am NZT) today to present evidence.

If the the panel finds Suarez guilty of assaulting an opponent, at best for Uruguay Fifa rules state that he should be banned for a minimum of two matches, but he could be suspended for up to 24 months.

A decision must be published before Saturday, when Uruguay plays Colombia in a round-of-16 match at Maracana stadium.

Uruguay's captain, Diego Lugano, accused Italy of making the most of the incident and claimed the scars on Chiellini's shoulder were old ones. "Chiellini is a bit of cry-baby and that does not sit well with me at all," he said.

Uruguay's manager, Oscar Tabarez, claimed he was the victim of a campaign orchestrated by the English media.

But having left the last World Cup amid controversy, handling on the line to deny Ghana a place in the semi-finals, Suarez now faces being ejected from this tournament. The first incident, in Johannesburg, turned him into a hero at home. This will be much harder to defend and Suarez has twice before been found guilty of biting opponents.

Fifa vice-president Jim Boyce said: "There is no doubt that Fifa must take this incident very seriously and take whatever action is deemed necessary. Luis Suarez is a fantastic footballer but once again his actions have left him open to severe criticism."

Fifa's disciplinary panel "is responsible for sanctioning serious infringements which have escaped the match officials' attention," the governing body said in a statement.

"Any type of proof may be produced," Fifa noted, including "reports from referees, declarations from the parties and witnesses, material evidence, audio or video recordings."

The heaviest sanction that Fifa has ever taken was an eight-match ban it imposed on Italy's Mauro Tassotti for breaking the nose of Spain's Luis Enrique during the 1994 tournament.

Having been eliminated in the group stages for the second successive World Cup, there was anger in the Italy camp that while Claudio Marchisio had been dismissed for a knee-high challenge, no action had been taken on Suarez. "It was absolutely clear-cut," said Chiellini. "It was ridiculous not to send him off.

"Then, after he bit me, he fell into an obvious dive because he knew very well what he had done and what the consequences would be. Claudio Marchisio's dismissal was ridiculous but even more so was the fact that Luis Suarez was not sent off.

"The gesture is clear. Referees study the players they are taking charge of and Suarez has a very clear history. We are not happy how things have gone and we were the only ones who deserve to go through into the next round."

Suarez had previously been banned for seven games for biting PSV Eindhoven's Otman Bakkal while playing for Ajax and 10 for biting Chelsea's Branislav Ivanovic at Anfield in April last year.

Cesare Prandelli, who resigned as Italy manager after the vicious, ill-tempered contest, said it was astonishing that no action had been taken. "I didn't see the incident but I did see the bite marks on Chiellini's shoulder," he said. "It is a real shame but a football match has been decided by some wrong choices."

Tabarez blamed the English press for making the most of the incident, saying: "Suarez, despite any mistakes he may have made, is the preferred target of certain media organisations that give him much more coverage for the mistakes he makes than for the successes he has."